The present invention relates to a loadlock and beam for use in pallet racks and is an improvement in the beam and loadlock disclosed in U.S. Pat. No. 3,741,405 issued June 26, 1973 to Kennedy McConnell and Raymond F. Juechter. A typical pallet rack is disclosed in U.S. Pat. No. 3,042,221 issued July 3, 1962 to George E. Rasmussen. As disclosed in the Rasmussen patent, a pallet rack comprises at least a pair of end frames having vertical uprights connected together by horizontal and diagonal cross braces. The end frames are interconnected by beams which have lug and slanted key slot connections with the upright. Locking of the beam to the upright is provided by a loadlock which includes a sliding bolt which has a shank extending through aligned holes in the upright beam end plate and bracket welded to the innerface of the end plate and a handle extending through a contoured movement-limiting slot in the beam wall.
The handle of the loadlock bolt has an enlarged head and is fitted with a spring metal retainer which maintains the bolt in the slot and also co-acts with the contoured edge surfaces of the slot to maintain the loadlock in a selected one of three positions of the slot. In the previous McConnell et al, patent, the loadlock was manually moveable between the loading position and the locking position, only two positions being disclosed in that patent, and as a consequence the loadlock was susceptible to becoming disengaged from the upright in the field. The loadlock and slot of the present invention remedy this shortcoming by providing a three position slot having a loading position and a shipping position and a locking position wherein manual movement of the loadlock between the shipping position and the locking position is substantially eliminated.
Prior art pertinent to the present invention includes the prior identified McConnell et al, and Rasmussen patents as well as the Fullerton, et al, U.S. Pat. No. 3,070,237, the Segal U.S. Pat. No. 2,280,084 and the Swiss Pat. No. 240,745. Copies of the foregoing U.S. Patents and Swiss Patent are provided herewith along with an English language translation of the Swiss patent.